Solar flares happen when energy stored in the twisted magnetic fields of the sun is suddenly released causing an explosion of plasma shot up from the sun's surface. This happens when the magnetic fields reconnect in active areas of the sun often seen as dark sun spots. This is where magnetic fields are at their strongest.

A solar flare may last just a few minutes or several hours. The energy from these solar flares is believed to be powerful enough to produce 100 billion atomic bombs and could power the entire United States for a million years! But solar flares should not alarm us Because all this activity happens low down in the sun's corona (outer surface).

This burst of electromagnetic radiation produced from these solar flares includes radio waves, x-rays and gamma-rays. Sometimes there will be a CME (see further down for explanation) associated with solar flares. Solar Flares and CME's can happen together or separately.

X-class solar flares

Solar flares are classified according x-ray brightness in the wavelength range 1 to 8 Angstroms.

3. C-class solar flares - small events: these have hardly any noticeable effects on Earth.

What is a Solar Maximum Cycle?

Solar activity operates on an approximate 11 year cycle. The sun is normally more active in the 11th year. It wasoriginally expected that a cycle would be completed in 2012. This is why some were expecting extra large solar flares in 2012.

Coronal Mass Ejections - CMEs

Magnetic fields in the sun can heat the sun's gases to tens of thousands of degrees. This energy can explode rapidlyout of the sun's corona (the unstable outer surface) at very high speeds ejecting up to 10 billion tons of ionised gas into the solar system at speeds of up to 2 million miles per hour. These events are called coronal mass ejections (CMEs). CMEs can take 2-3 days to reach earth and may happen once or twice a week, sometimes more.

The difference between solar flares and CME’s

CME’s are different to solar flares because the plasma actually lifts off from and leaves (is ejected from) the surfaceof the sun. It is then carried by solar winds into the solar system and can be as big as the sun itself. A CME can result in magnetic storms when its gasses interact with the Earth's magnetic field. This distorts the shape of our magnetic field and speeds up the electrically charged particles that are trapped inside.

What are the potential dangers of CME’s for earth?

Coronal mass ejections can cause magnetic storms when they interact with the earth’s magnetic field. You can see the effects in (1) an aurora - the northern lights seen at the North Pole – this depends on the sun’s magnetic configuration at the time, and (2) damage to ground based technology, disrupted radio communication, damage to satellites, localised blackouts due to an electrical grid going down and mild radiation for astronauts in the affected zone.

Blackouts can have serious consequences and it could take months to get a citywide electrical grid working again. It is not hard to imagine that chaos that could result when are large poplulated area is suddenly without electricity for a long period of time.

Examples of CME’s hitting earth and their effect

One such blackout was on March 13, 1989 when Quebec in Canada experienced a nine hour blackout. In November 4, 2003 a CME associated with the X Class solar flare estimated to be an X45, left the sun traveling at 2300 kilometres per Second (8.2 million km/h). It was so powerful that it overloaded the sensors measuring it. Its effect on the planet was minimal because the full blast of the CME was directed away from the earth. But there was potential to do significant harm if we got a direct hit.

Is earth in danger at this time?

December 21, 2012

Based on the present activity of the sun, NO, we are NOT in any expected danger for December 21, 2012 or anywhere near that date. There are two reasons why we should not expect extra large solar flares or coronal mass ejections in 2012 (and especially on December 21, 2012).

1.…. The next solar maximum cycle that produces these extra large flares and CMEs, is not going to happen till around May 2013! Some are now even saying 2014

2….In May 2013 when the sun is expecte to reach its highest level of activity in its most recent 11 year solar cycle, it is predicted that the sun will have the lowest number of sunspots (which cause solar flares) since 1928! So while solar activity may peak as many expect around May 2013, it’s not going to be a biggie!

“Shields up Scotty!”

OK, so if you’ve never seen the original Star Trek, the heading for this section won’t mean anything. Moving on… Evenif an extra large CME did come our way, we are protected by our magnetosphere, ionosphere and atmosphere from serious harm. Well, we have been protected for a long time but the shields are no longer at 100%. Here’s why…

In December 2008, NASA discovered a breach (a hole) in these shields. This makes it possible for charged solar winds to build up their presence and load the earth’s magnetosphere for a sizeable magnetic storm.

However, in our favour, with the advancement of technology, warning systems are now being put in place so that vulnerable electrical grids can be shut down till the danger is over.